Documentation
Crimp terminals

Cable Topics

Crimp terminals for cables

Crimp terminals lock to the end of a wire and attach to an electrical connection such as a screw or terminal block. There are tons of different styles out there, but we found a handful that every Chinese cable manufacturer stocks. This is important because while reels of crimps are cheap, each crimp uses different tooling and manufacturers only buy tooling for the most common crimps.

In the previous post we covered commonly used JST and Molex compatible parts from the Shenzhen markets. These connectors come in two parts: a metal crimp that attaches to the wire, and a plastic crimp housing that holds all the crimps in place. This post looks at common crimp terminals that don’t use a plastic housing. Get the sample kit here, or build your own custom cables here.

Ring terminals

These super common crimps attach to a bolt or screw terminal block. Four sizes are super common in the market and all fit a corresponding metric bolt size: 3.2mm (M3 bolt), 4.2mm (M4), 5.2mm (M5), 6.2mm (M6). Smaller and bigger sizes are available, but the crimps are rarely stocked so you’ll generally be on the hook for MOQ if you stray from this safe range.

Our manufacturer recommends 18AWG wire for all crimp terminals.

Spade terminals

Spade or fork terminals attach easily to a bolt or screw terminal without fulling removing the screw from the terminal. We only found these in 3.2mm (M3) and 4.2mm (M4) in the market.

These work with common screw terminals and grounding bolts, but we found these really nifty PCB mount connectors (through-hole) with a single screw terminal. The manufacturer has a range with parts numbers from PCB-1 to PCB-14 that vary primarily in the height of the leads. PCB-2 is the most compact and lowest profile version, so we’ve been working with it.

Our manufacturer recommends 18AWG wire for all crimp terminals.

Blade terminals

Male and female blade terminals connect cables to board mount connectors AND cables to other cables. Available in multiple sizes, but 2.8, 4.8 and 6.3 are the most common.

There are multiple type of terminal blocks for connecting female blade connectors to PCBs or wiring harnesses. We found single PCB mount connectors (through-hole) for use with female blade crimps. The smallest versions (2.8) use 0.5mm thick metal, while the 4.8 and 6.3 version use thicker 0.8mm metal. The two bigger connectors have offset tabs to provide additional stability.

Our manufacturer recommends 18AWG wire for all crimp terminals.

Other crimp terminals

A lot of available crimp terminals are missing from this list: male and female bullet connectors, right angle blade connectors, etc. A reel of these crimps is not expensive, but most cable manufacturers don’t have the proper tooling work with them in their crimping machines. Crimp tools can range from $100 to $1000s, depending on the machine and if the manufacturer has to customize the tools.

If you’re looking to do low volume cheaply, it’s always best to use what multiple manufacturers and distributors have available in the market.

Insulated covers

All three types of crimp terminals have compatible insulators in multiple colors. We’re not yet equipped to offer these in the dirty cables creator.

Maximum ratings

Please note that we’re unable to provide maximum ratings at this time. Our cable suppliers don’t have datasheets for the common “duff” stuff they’re using, so you’ll need to do the same due diligence on the final cables that you would if buying directly in China yourself.

We’ll need to find our own crimp terminal manufacturer and supply parts to the cable maker ourselves to get properly rated parts.

Touch it yourself: Dirty Terminals Sample Pack v1.0

Buy the kit. Can’t wrap your head around it without getting your hands on these parts? Don’t worry, we’ve got you covered. All these crimp terminals and mating connectors are available in the Dirty Terminal sample pack. Grab it in the store for $4.95.